All along the Grand Concourse, you find people walking, talking and listening to their cell phones. But in the coming months to come, you may find them listening to their cell phones while standing in front of and staring at trees.

“Each has its own story to tell,” said Katie Holten, referring to the 100 trees along the Grand Concourse that she has made a part of the Bronx Tree Museum, a project she was commissioned to create as part of the 100th anniversary celebration of the Grand Concourse.

The project was organized by the Bronx Museum of the Arts and Wave Hill, but Holten is the artistic mastermind behind this “museum without walls.” Although it is mostly invisible — only six signs indicate its presence along the Concourse from 138th Street to Mosholu Parkway — the public work of art is a museum-goers dream. There are no lines, it’s free and it never closes. 

The museum consists of 100 existing trees along the Concourse that were picked by Holten. At each tree there is a tiny plaque with a phone number and extension to call for a brief glimpse into life on the Concourse both past and present, and in both English and Spanish. Voices ranging from historians and local singers, to schoolchildren and an ex-Yankee, provide the perspectives that are centered around Holten’s theme of tree rings, or layers, of history.

“It’s historical, but it’s about the present,” Holten said. “People live here now and it’s their story.” Holten hopes people discover some of the surprises she did while researching, like the fact the Concourse was completely covered with trees before being paved to connect densely-populated Manhattan with the then more country-esque Bronx. “Nature is everything, it’s all connected,” Holten said. “People think you have to leave the city to find nature, but it’s right here.”

The idea of an outside museum just made sense to Holten, who is originally from Ireland, because of what she describes as the New York and Bronx phenomenon of “just hanging out on the streets.” 

From now until Oct. 12, Holten encourages the curious to use their cell phones on this self-guided tour that can begin and end at one’s will, although the complete walk is estimated to take two and a half hours. Even those equipped with a museum-provided map may be left wondering where this wall-less journey is, but that’s just the way Holten wants it.

“You could walk up and down and not see it,” Holten said. “I like that,” she added. “It’s about roots and what’s underground — not seen.” 

Ed. note: For more on the Bronx Tree Museum, including a map, visit www.treemuseum.org.